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ClearSky

clear-sky.com · West Palm Beach, FL

“Deep, decade-plus operator relationships in cybersecurity and the energy transition give ClearSky superior deal flow, diligence quality, and the ability to accelerate portfolio company growth through strategic introductions.”

$1M – $60M
Check Size
Leads & Follows
Lead Tendency
$1B
AUM
01Investment Thesis

Deep, decade-plus operator relationships in cybersecurity and the energy transition give ClearSky superior deal flow, diligence quality, and the ability to accelerate portfolio company growth through strategic introductions.

Exclusion Criteria

Not a seed investor; avoids sectors outside cybersecurity and energy transition.

02Investment Team
AW
Alex Weiss
CEO, Co-Founder & Managing Partner
JH
James Huff
Co-Founder & Managing Partner
ES
Erik Straser
Partner
RR
Robert Rauch
Partner
RC
Ryan Crum
Partner
GN
Guy Nizan
Venture Partner
HS
Howard Shecter
Executive Partner
JW
Joseph Wright
Chairman of the Investment Committee
DF
Daniel Furey
Partner, Head of Global Capital Formation
NB
Nick-Anthony Buford
Managing Director & General Counsel
AS
Austin Summers
Senior Vice President
VN
Vince Nicchi
Controller
AN
Anjali Nagaraja
Associate
OS
Owen Santos
Analyst
03F4 Research Brief

ClearSky Research

Investment Thesis

ClearSky Advisors is a venture capital and growth equity fund manager headquartered in West Palm Beach, Florida, that has managed approximately $1 billion in capital commitments over more than a decade (founded 2012). The firm invests exclusively in two sectors where its partners claim operator-level, insider expertise: cybersecurity and the energy transition. ClearSky's stated thesis is that its deep, long-standing relationships with utilities, critical-infrastructure operators, and enterprise security buyers give it superior deal flow, diligence quality, and the ability to accelerate portfolio companies' revenue growth through strategic introductions. The firm is a member of the Global Impact Investing Network (GIIN) and a signatory to the UN Principles for Responsible Investment and the Venture Climate Alliance, reflecting an ESG-oriented approach to the energy transition side of the portfolio.

Stage Focus

ClearSky invests across Series B through growth-stage rounds, with occasional smaller convertible-note top-ups into existing portfolio companies. It is not a seed investor. Recent 2025-2026 activity spans Series B (Guardz, Mitiga extension, XGS Energy), Series D (Ubicquia), late-stage growth rounds (Renew Home), and convertible notes (EdgeQ, Query.AI).

Check Size

Typical check sizes range from roughly $1M-$2M for smaller convertible-note or follow-on participations (Mitiga: $1M of a $6.6M extension; EdgeQ: $1.5M of an $11M note; Renew Home: $2M of a $50M round) up to $20M-$56M+ when leading a round (Cleartrace: led a $20M round in 2022; Guardz: led/co-led a $56M Series B in 2025). ClearSky has also participated alongside larger syndicates in $100M+ rounds (Ubicquia's $106M Series D).

Lead Tendency

Mixed ("both"). ClearSky has led or co-led several rounds historically (Cleartrace, Guardz, XGS Energy Series B) but frequently takes smaller participating positions in larger syndicated rounds, especially for follow-on investments into existing portfolio companies (Renew Home, EdgeQ, Mitiga, Query.AI).

Recent Activity

ClearSky has been very active through its Spring 2026 newsletter reporting period:

  • April 2026: Invested $2M in Renew Home's $50M growth round (virtual power plant / demand-response platform)
  • March 2026: Backed Query.AI's convertible note round
  • February 2026: Co-led XGS Energy's Series B (New Mexico geothermal project with Meta)
  • February 2026: Participated in Ubicquia's $106M Series D (smart grid / intelligent lighting)
  • January 2026: Portfolio company Altamira was acquired by Parsons for $330M plus a $45M earn-out
  • December 2025: Invested $1.5M in EdgeQ's $11M convertible note
  • December 2025: Invested $1M in Mitiga's $6.6M Series B extension
  • October 2025: Portfolio company Inky was acquired by Kaseya
  • September 2025: Portfolio company Qwiet AI was acquired by Harness
  • June 2025: Led/co-led Guardz's $56M Series B
  • November 2024: Announced Fund IV, targeting up to $500M

Fund status: actively deploying. ClearSky is currently investing out of multiple named vehicles referenced in portfolio company descriptions, including "Security I," "Power II," and "Fund IV."

Portfolio Highlights

Since 2012, ClearSky has invested in more than 30 cybersecurity companies and dozens of energy-transition companies, with a reported ~60% exit rate across 21 acquisitions and 2 IPOs. Notable exits and public outcomes include Mandiant (f.k.a. FireEye, acquired by Google), Cylance (acquired by BlackBerry), CloudGenix and Demisto (both acquired by Palo Alto Networks), Verodin and Preempt Security, Databricks (f.k.a. Okera), IntSights (acquired by Rapid7), Nikola Corporation (Nasdaq IPO), Nextracker (Nasdaq IPO), Altamira (acquired by Parsons, Jan 2026), Inky (acquired by Kaseya, Oct 2025), and Qwiet AI (acquired by Harness, Sep 2025). Active notable names include Arctic Wolf Networks, BigID, AppOmni, Optiv, Guardz, Mitiga, Query.AI, Ubicquia, Renew Home, EdgeQ, XGS Energy, Harness, Human (bot/fraud mitigation), Mainspring Energy, Cleartrace, and Spruce Power.

Team

  • Alex Weiss — CEO, Co-Founder & Managing Partner
  • James Huff — Co-Founder & Managing Partner
  • Erik Straser — Partner
  • Robert Rauch — Partner
  • Ryan Crum — Partner (joined from Apollo Global Management, where he was Chief Security Officer/CTO; prior roles at JPMorgan, TIAA-CREF, PwC)
  • Guy Nizan — Venture Partner
  • Howard Shecter — Executive Partner
  • Joseph Wright — Chairman of the Investment Committee
  • Daniel Furey — Partner, Head of Global Capital Formation (joined from Global Infrastructure Partners/BlackRock, UBS, Merrill Lynch)
  • Nick-Anthony Buford — Managing Director & General Counsel
  • Austin Summers — Senior Vice President
  • Vince Nicchi — Controller
  • Anjali Nagaraja — Associate (promoted from Analyst in 2023; contributed to EdgeQ, Mitiga, Guardz)
  • Owen Santos — Analyst, focused on the firm's AI strategy

Decision Process

ClearSky operates with a formal investment committee (chaired by Joseph Wright) and a multi-partner structure, indicating a partnership/investment-committee decision process rather than a solo-GP model.

Founder Preferences

Portfolio commentary emphasizes technical, mission-driven founders building disruptive, deployable technology in cybersecurity and energy infrastructure — often with clear enterprise or utility customer traction (e.g., Query.AI's utility-provider deal, XGS Energy's Meta partnership, EdgeQ's public-safety network deployment) rather than pure early-stage, pre-revenue bets.

Geographic Focus

Headquartered in West Palm Beach, Florida (525 Okeechobee Blvd, Suite 800, West Palm Beach, FL 33401). Portfolio is primarily US-based with some international investments (e.g., IntSights, Guardz, and Solebit in Israel; ClimateTrade in Spain).

Strategic Partnerships

ClearSky partnered with a group of industry veterans to establish Clarum Advisors, a strategic consulting group focused on accelerating the global energy transition, supporting thesis development and portfolio company strategy/operations.

04Selected Portfolio
Aerospace & Defense
Sceye
Climate & Sustainability
Aquion Energy·BHI Energy·ClimateTrade·Fermata Energy·Modular Wind Energy·Verengo
Energy & Power
NEXTracker·ClearTrace·Mainspring Energy·Greensmith Energy Management Systems·Novinium·PowerPhase·Utility Innovation Holdings·Renew Home·XGS Energy
Enterprise Software
Databricks·Nikola·Harness·CloudGenix·Altamira·AutoGrid Systems·Beacon AI·Diamanti·iControl Networks·IS5 Communications·Noda·ProcessUnity·Sentient Energy·Space-Time Insight·Field Group·Ubicquia·EdgeQ
Fintech & Payments
Spruce Finance·T-Rex Group
Manufacturing & Industrial
Pike Corporation·Systems Control
Security & Cybersecurity
Mandiant·Cylance·Arctic Wolf·BigID·AppOmni·Optiv·Qwiet AI·HUMAN Security·IntSights·Demisto·Inky Technology·ProtectWise·Verodin·Lasso Security·Accurics·Authentic8·Blue Lava·Capsule8·CloudKnox Security·Fortress Security Holdings·Phylum·RedOwl Analytics·Resilient Systems·Respond Software·SecurityAdvisor Technologies·Skout Cybersecurity Holdings·Solebit Labs·Query.ai·Mitiga·Guardz
Other
Preempt Security·SecZetta
Open the full portfolio→
05Recent Updates

Fresh signals from public announcements, essays, and portfolio activity.

See full activity (14) →
Owen Santos joined ClearSky as Analyst, focused on the firm's AI strategy and implementation.
TEAM CHANGE·clear-sky.com
Added recently
Daniel Furey joined ClearSky as Partner and Head of Global Capital Formation after roles at Global Infrastructure Partners (BlackRock), UBS, and Merrill Lynch.
TEAM CHANGE·clear-sky.com
Added recently
Ryan Crum joined ClearSky as Partner after serving as Chief Security Officer and CTO at Apollo Global Management.
TEAM CHANGE·clear-sky.com
Added recently
Power II invested $2M in Renew Home's $50M growth round to scale its virtual power plant platform.
INVESTMENT·clear-sky.com
APR 2026
Security I backed Query.AI's convertible note round following a major enterprise utility deal.
INVESTMENT·clear-sky.com
MAR 2026
06Frequent co-investors
CO
Capital One Ventures
Both backed 3 of the same companies
Verodin, Cylance, Harness
CI
Cisco Investments
Both backed 3 of the same companies
Mitiga, BigID, Harness
SV
SYN Ventures
Both backed 3 of the same companies
Mitiga, Query.ai, Qwiet AI
CC
Cota Capital
Both backed 2 of the same companies
BigID, Harness
CC
Crosslink Capital
Both backed 2 of the same companies
Verodin, Harness
Find the investors for your round→
Quick Reference
Check Size
$1M – $60M
Stages
Series B · Series C · Growth
AUM
$1B
Decision
Investment Committee
Involvement
Board Seat
Location
West Palm Beach, FL
Sector Focus
Mobility & TransportationClimate & SustainabilitySecurity & CybersecurityEnergy & Power
Models
Cybersecurity SoftwareEnergy InfrastructureGrid Modernization
Technology
AI-Powered SecuritySmart GridGeothermal
See all Mobility & Transportation investors →See all Climate & Sustainability investors →See all Security & Cybersecurity investors →
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Focus Areas
Mobility & TransportationClimate & SustainabilitySecurity & CybersecurityEnergy & Power

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F4 Intelligence Report · Last Researched September 4, 2026F4 Research Engine